A teenage girl from Owatonna has died after coming down with flu-like symptoms nearly a week ago. And while it'll be several weeks before the cause of her death is confirmed, it could be a sign of a harsh season for the flu in Minnesota.

Shannon Zwanziger, 17, a senior at Owatonna High School, died Tuesday at the Mayo Clinic in Rochester, the Owatonna People's Press reports.

Her father, Terry Zwanziger, said Shannon became sick last Wednesday and stayed home from school for a few days. She had a fever and developed a sore throat that made it hard for her to eat or drink anything, according to the People's Press.

Shannon's parents took her to see a doctor and had her tested for strep throat. But her condition worsened and on Tuesday, Shannon's heart stopped beating while she was at home in her mother's arms, according to KSTP.

Shannon's mother began CPR until paramedics arrived and took her to the Owatonna Hospital. Shannon was then flown by helicopter to Mayo, but she could not be revived.

Family members said Shannon had no health issues that would have put her at higher risk of dying from the flu. Influenza isn't usually fatal for teenagers unless they have other complications, according to the Star Tribune.

The flu has been running rampant through Owatonna High School lately, according to principal Mark Randall. About 10 percent of the school's 1,500 students reported they were sick on Thursday, Friday and Monday.

Randall told the People's Press the absentee rate is twice as high as it was last year at this time.

Statistics from the Minnesota Department of Health bolster that claim; they show that influenza cases are higher in southern Minnesota than in other parts of the state right now.

It's not yet known for sure whether the flu was the cause of Shannon's death. Health officials say it'll take several weeks of testing to determine that. Nevertheless, it serves as an indicator that this winter's flu season is likely to be harsher than normal.

“Though we cannot predict what will happen the rest of this flu season, it’s possible we may have a season that’s more severe than most,” Dr. Tom Frieden, director of the U.S. Centers for Disease Control and Prevention, said last week.

The flu strain that's circulating this year, H3N2, typically results in more people needing to be hospitalized, and more people dying, according to the Centers for Disease Control and Prevention. And the flu vaccine that's being administered this year isn't as potent against H3N2, either.

Still, health officials are urging people to get a flu shot anyway.

“The influenza vaccine may not provide complete protection, but it can provide protection for three or four strains of the influenza virus,” said MDH spokesman Doug Schultz, according to the People's Press. “It’s the best tool we have to prevent influenza.”

Shannon Zwanziger was "full of life, full of fun," her aunt, Brenda Baska, told the Star Tribune, adding that her family is in shock over her death.

Friends of the family have begun raising money on the youcaring.com website to help the Zwanzigers with expenses, including the travel costs for Shannon's sister who lives on a U.S. military base in Japan.